1. Field of the Invention
This invention pertains to the field of household and personal safety appliances. More particularly, this invention pertains to safety devices used in bodies of water such as swimming pools, to sound an alarm upon the unauthorized entry into the pool by some person or animal.
2. Description of the Prior Art
Backyard swimming pools are popular and are increasing in number throughout the United States. While popular, they present a serious hazard to children and small animals who enter unattended pools. Numerous instances of child drowning have been reported. In virtually all of these cases, the child has entered the pool at times when no adult or other responsible individual attended the pool to see to the child's safety.
Safety precautions such as surrounding the pool with fences have not stopped the continual drowning hazard of the pools. Children climb the fences or find ways of opening the gates. Even flood lights do not seem to have made the pools much safer. Insurance rates for dwellings with outdoor swimming pools are high and appear to be increasing due to the ever-present danger of children entering the pool and drowning.
The prior art has attempted to deal with these swimming pool hazards by utilizing floating alarms that would actuate upon wave action generated by the unauthorized entry of a child or animal into the pool. For instance, in a patent to White, U.S. Pat. No. 3,276,007, a floating plate supports an electric alarm having an actuating switch positioned above a pool of liquid metal such as mercury so that tilting of the base caused by wave action closes the switch and actuates a horn or other audible alarm. In a patent to O'Connor, Jr., et al, U.S. Pat. No. 3,038,151, a hollow, floatable vessel encloses a support having a centered depression wherein a ball is seated. Wave action tilts the vessel and causes the ball to roll out of the depression and fall to a lower surrounding curbing that leads down to a mechanical arm that closes, under weight of the ball, an electric switch to actuate a battery-powered alarm.
While these prior art devices have attempted to solve the problems attendant with swimming pool hazards, they possess certain drawbacks that have prevented them from becoming popular. For instance, in White, slight ripples in the surface of the swimming pool caused by wind may cause the mercury to slosh up and down in the switch and cause the alarm to sound when no one has entered the pool. In addition, one cannot observe the operability of White because the mercury switch, battery and other components are enclosed in an opaque container. Further, the mercury switch is not adjustable so as to be adaptable to swimming pools located in areas of either quiet winds or substantial winds and the constant intermittent sounding of the alarm due to wind rocking will possibly annoy the home owner to the point where he or she removes the device from the swimming pool thereby removing the ability of the alarm to perform its function.
O'Connor, Jr., et al, possesses additional drawbacks; for instance, the interior is substantially complicated so that rain dropping or water splashing into the device could damage one or more of the functional parts thereof. It is also complicated and thus expensive. In addition, observation cannot be made of the position of the ball in the depression so that one must assume that by dropping the ball in through the top opening will position the ball properly. Further, in O'Connor, Jr., et al, the device must be removed from the pool and inverted to re-arm the mechanism for subsequent use and the opaque nature and overlying structure of the device prevents visual observation from the outside as to whether or not the device is really armed.
Accordingly, there is a continuous and on-going need for an inexpensive wave-actuated swimming pool alarm that is visually observable in its armed position, is adjustable to various pool sizes and wave actions due to surrounding winds, is re-armable without removing from the swimming pool and wetting the hands, and that is amenable to having long acting power devices such as solar power compliment its power components.